Markdown is one of many ways, one of the better ones, of writing HTML without writing HTML. You use a more natural style to markup text and feed it to a Markdown conversion script which generates the corresponding HTML. Many sites on the net today natively (or via plugins) support Markdown markup (e.g: Tumblr). There are already a few cheatsheets (1, 2) for Markdown, but I made this one up anyway, since I wanted a different layout and something that fits in one A4 or Letter sized sheet of paper.

Below are standard (dark) and light versions, the latter more suitable for printing.

[…] I don’t have to look far for examples. Vi and Emacs are in typical use editors for programmers. Consider recent developments in text editing. The preference these days runs against complex multi-function tools with a zillion knobs, bells and whistles, to “distraction free” editors and simple styling methods such as Markdown. […]